<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <title>app</title>
    <style>
      .clearfix::after{
          content:'';/*内容为空*/
          display:block;/*显示为块状元素*/
          width:0;/*宽0*/
          height:0;/*高0*/
          visibility:hidden;/*隐藏*/
          clear:both;/*左右不允许有浮动元素（左右浮动都清除）*/
      }
      .clearfix{ 
                  zoom:1;
      }
      *{margin: 0;padding: 0;text-decoration: none;list-style: none;}
    </style>
  </head>
  <body>
    <div id="app"></div>
    <script src="./build.js"></script>
  </body>
</html>
